Shaping apparatus



- Jan. 29, 1935. G. E. DISNEY 1,989,474

I SHAPING APPARATUS.

Filed Oct. 15,1932

666F719 15 Di n y Patented Jan. 29, 1935' 1,989,474

UNITED STATES PATENT OFFICE.

SHAPING APPARATUS George E. Disney, Akron, Ohio, assignor to WingfootCorporation, Wilmington, Del., a corporation of Delaware ApplicationOctober 15, 1932, Serial No. 637,900 8 Claims. (01. 182) This inventionrelates to apparatus for shaping which the tube is to be employed, andat their rubber articles and more particularly relates to outercircumferential edges with a circumferenapparatus for giving apreliminary set or shape to tially extending strip. A roughdoughnut-shaped unvulcanized inner tubes of the character to be innertube is thus produced which is preferably employed in conjunction withpneumatic tires. given a set or a preliminaryshaping prior to its 5Heretofore in producing certain rubber articles, insertion in thevulcanizing mold to avoid the such as inner tubes, considerabledifficulty has difiiculties'setforth above. a been experienced inshaping the unvulcanized ar- It is an object of the present invention toavoid ticles so that when the same are placed in the and overcome thedifficulties encounteredin pro-' v vulcanizingmold there will be no spotcuring ducing rubber articles as described above bythe 10 v of thearticle due to premature contact of certain provision of shaping meansadapted to give the portions of the article with the mold. Again itrubber articles a preliminary set or shaping prior has been found thatif the unvulcanized article to insertion thereof in the vulcanizingmold. is non-uniformly placed in the curing mold there Another object ofthe invention is to provide 35 may be a flow of rubber during thevulcanizing apparatus for the preliminary shaping of unvulprocess whichis apt to produce an article having canized super-balloon inner tubes.walls of non-uniform thickness. It also has been Another object of theinvention is to provide found that when unvulcanized rubber articles aremechanism whereby rubber articles can beformed placed in the curingmolds, a pinching of the arto substantially their completed orvulcanized ticle by the mold is apt to occur if the .unvulshapebya prliminary ap t n n-vul anizcanized article has been given no preliminaryset. ing operation. v I

The foregoing difficulties are particularly prev-Anotherobjectoftheinvention is to provide a alent in the production ofinner tubes for superlight weight, inexpensive,- easily operatedappaballoon pneumatic tires of the type which has ratus wherebyinflatable articles such as inner 2 recently proven popular forautomobiles and other tubes can begiven an initial blow-up or shapingbecause the super-balloon inner tube is of com- Another object of thepresent invention is to paratively large cross-sectional dimensions asprovide a wooden shaping .mold for giving a supercompared with its beaddiameter. Thus if the balloon inner tube an initial set prior to thevul- 3 inner tube is made by an extruding operation canizationoperation. V 0 with the ends of a length of the extruded tube Theforegoing and other objects of the invenbeing thereafter joinedtogether, it will be evident tion are achieved by the apparatusillustrated in that, when inflated, the outer portion or tread theaccompanying'drawing, wherein: wall of thetube will have to expand aconsider- Fig. 1 is a plan View .ofone form-of the apparatus ablygreater amount than willthe inner portion comprising the presentinvention, with a portion 3 or base wall. If this expanding operation isperthereof being broken away to better illustrate the formed in thevulcanizing mold it will :be obvious, details of its. construction; j t,Y a that some difficulty may be experienced because Fig. 2 isa crosssectional view ofthe apparatus of the fact that-the inner periphery ofthe tube shown in Fig. v1 taken on line'II- -II thereof, with willcontact prematurely and at asomewhat the parts in separated relation andgreater interval of time with the-hot: surfaces of Fig; 3' is'a,crossesectional viewitaken on line the vulcanized mold. Again thevulcanizing mold IIIIII of Fig.; 1,. with. the parts assembled tois aptto cause a non-uniform expansion of the ge'ther- I 5' outer portion orperiphery of theinner tube.-- Referringnowi tothe drawing whichillustrates 4 If the super-balloon inner-tube produced is one one formof the cinvention,the numeral .10 indiin which the bead diameter ismaterially smaller cates an inner-"tube havinga conventional valve thanthe cross-sectional diametenas is the case stem 11 associatedwithittofacilitate inflation. in an airplane tire which mountsdirectlyupon The initial set or'shape of the'inner tube 10 is asupporting hub,-then other methods of proaccomplished by means of- 'apair of compliland vehicles, as well as aircraft. This has beenoperation prior to the'curing thereof. 25

ducing the inner tube may be employed. By one mentary mating moldmembers Hand 15 which 50 of these methods it has been the practice tomake are preferably formed of light weight material up an inner tubefrom two flat centrallyflapersuch as wood. p tured discsof rubber whichare joined at their "The mold members 14 and 15 are'endless and centralapertures with a short length of tubing of annular: and mayprefe'rab-ly.beformed male and approximately the bead diameter of the tire in femalerespectively, as illustrated in the draw- 55 the slot 19 and ing, toinsure the proper concentric alining and coaction thereof. These membershave their outer peripheries grooved so that, when assembled together,they present an annular cavity 18 of substantially semi-circularcross-section. As will be seen from the drawing, the lower or femalemold member contains more than half of the cavity 18 and thereby isbetter adapted to initially receive and hold the inner tube 10 to beshaped, and to prevent pinching of the inner tube when the two moldmembers are brought together. The valve stem 11 in the inner tube 10extends through a suitable slot or opening 19 in the male mold member14. This slotted opening 19 allows the male mold member 14 to be droppedin position over the tube and into cooperating relation with the femalemold member 15 after the inner tube-10 has been ini-- tially placed inthe portion of the cavity 18 upon the female mold member 15. necessaryor advisable to provide a small slotted opening inthe female mold member15 to assist to insure the proper gripping of the valve stem 11. i

In order to limit the expansion .of the sidewalls of the tube 10,themold members 14 and 15 are provided with additional shaping elementsin the form ofring-like plates 22 and 23. These plates 22 and 23 arepreferably made of light weight strong sheet metal and may be providedwith flanged outer peripheries 24 and 25 respectively which function tostrengthen the same. The plates are adjustably secured to the moldmembers 14 and 15 through the agency of suitable means such as anglebrackets 28 and 29 which are bolted as at 30 and 31 to the plates 22 and23. The legs of angle brackets 28 and 29 adjacent the mold members 14and 15 are slotted to receive screw means 34'and 35 which serve toadjustably secure the brackets and thus the plates 22 and 23 to the moldmembers.

. Means are provided for normally locking the mold members 14 and 15together during the shaping or setting operation, which means mayobviously take a plurality of forms. As illustrated in the drawing,these means may comprise alever 38 pivotally mounted as at 39 upon abracket 40 secured to one of the mold members, preferably the upper ormale mold member 14. An apertured plate 42 is secured to the other moldmember 15, the aperture being adapted-to receive the hooked end of thelever 38. 'A spring 43 is ordinarily provided to urge the lever 38toward the locking positionl v It is believed that the operation of theapparatus will be apparent from the foregoing description. However, abrief rsum thereof follows:

With the upper or male member 14 removed theinner tube, which has beenconstructed in any one of the manners discussed above or by other knownmethods, is dropped down over the upwardly extending portion of thefemale mold member 15 and the tube is initially positioned in the cavity18 as illustrated in Fig. 2. There is, however, substantially no air orother inflating fluid in the tube at this time. The male mold member 14is then brought over the assembly and lowered in position with respectto the female mold member 15. The slot 19 in the mold member 14 is, ofcourse, positioned so that the same will slide down. over the valve stem11 of the inner tube 10. Thereafter the plates 22 and 23 are adjustedvertically to the desired position if this has not been done before.This operation is, of course, possible due to theedjustable conanddescribed.

It may be found nection provided by the slots in the angle brackets 28and 29.

The inner tube 10 is now inflated through the valve stem 11 to anydesired pressure to cause the tube to swell up to the toroidal shapedefined by the cavity 18 and side plates 22 and 23, whereupon the wholeassembly is allowed to sit for any length of time desired. By way ofexample, it may be stated that in practice, about three minutes havebeen found sufficient to effect a set of .the rubber tube in theapparatus illustrated This time period may vary, however, according tothe size of the tube and properties of the compound from which it isformed. Thereafter the member 14 may be removed, leaving the tube 10free to be released fromthe cavity 18, and, due to the preliminarysetting or shaping, the tube can be readily placed in a vulcanizing moldwithout spotting or improper stretching and the same is thereafter curedin the usual manner.

While the. invention has been particularly illustratedand described asbeing adapted for use in conjunction with inner tubes for superballoontype pneumatic tires, nevertheless it will beapparent that theprinciples thereof are readily applicable to the preliminary shaping ofsubstantially any inflatable rubber or plastic object. It will,moreover, be understood that while applicants apparatus preferably doesnot completely enclose the article to be shaped, the inventioncontemplates shaping in this manner as well, or. in other ways whichfunction to produce the desired set or initial shaping of the rubberarticle. In this respect the position of the adjustable plates 22 and.23 can be varied to control the particular type of initial setting orshaping to be given the rubber article.

From the foregoing it will be evident that mechanism has been providedby the present invention to initially form rubber articles while in theunvulcanized state whereby the vulcanizing operation performed thereonis expedited and improved. This mechanism is designed to'be light inweight, inexpensive, and easily and quickly handled by the inexperiencedworkman.

While the particular cooperating relation of the mold members 14 and 15has been described, as has been the material from which the mold membersare produced, nevertheless it will be apparent th t these particularfeatures of the specific embodiment of the invention described can bewidely varied without departing from the present invention. In a likemanner, the shape and, relative amount of cavity, in each of the matingmold members can be varied to obtain the desired shape and the necessaryinitial holding functions of the apparatus. In fact, any or all of theforegoing and other changes may be made without departing from thespirit of the invention as defined by the appended claims.

What I claim is: 1 I 1. Tube forming apparatus comprising a pair ofwooden, mating mold members having complementary grooves providing acavity adapted to receive and engage the inner periphery of anunvulcanized unformed rubber inner tube, a plate surrounding each ofthe-mold members and serving to limit sidewise'" expansion of the tubewhen inflated without engaging the outer periphery of the tube, meansadjustably and individually securing the plates to the mold members, andmeans for releasably securing the mold members together.

.2. Tube forming apparatus comprising a pair of mating mold membershaving complementary grooves providing a cavity adapted to receive andengage only the inner periphery of an unvulcanized unshaped rubber innertube, a plate surrounding each of the mold members and serving to limitsidewise expansion of the inner tube when inflated without engaging theouter periphery of the tube, means adjustably and individually securingthe plates to the mold members, and means for releasably securing themold members together.

3. Tube forming apparatus comprising a pair of mating mold peripheralgrooves providing a cavity adapted to receive and engage only the innerperiphery of an unvulcanized unfonned rubber inner tube, a plateassociated with each of the mold members and extending radially outwardtherefrom at each side of said cavity and serving to limit sidewiseexpansion of the inner tube to be shaped, and means for releasablysecuring the mold members together.

4. Tube forming apparatus comprising a pair of annular mating moldmembers having complementary peripheral grooves providing a cavityadapted to receive and partially surround an unvulcanized unformedrubber inner tube, a plate extending radially outward from each of themold members adjacent each side of said cavity and serving to partiallyconfine the article to be shaped, and means adjustably and individuallysecuring the plates to the mold members.

5. For giving preliminary set to an unvulcanized rubber inner tube, ashaping apparatus comprising a pair of mating annular body membersjointly formed with a peripheral groove adapted to receive the innertube and snugly to members having complementary,

periphery of said tube when expanded, and a pair of annular flangesassociated one with each of the body members and adapted to limitsidewise expansion of the tube without confining the outer peripheralportion thereof.

6. For giving preliminary set to an unvulcanized rubber inner tube, ashaping apparatus comprising a pair of mating annular body membersjointly formed with a peripheral groove adapted to receive the irmertube and snugly to seat the inner periphery of said tube when expandedbut leaving the outer periphery of the tube free and unengaged, one ofsaid members containing more than half of the jointly formed groove.

7. For giving preliminary set to an unvulcanized rubber inner tube, ashaping apparatus comprising a pair of mating annular body membersjointly formed with a peripheral groove adapted to receive the innertube and snugly to seat the inner seat the inner periphery of said tubewhen expanded without confining the outer peripheral portion thereof,one of said members containing more than half of the jointly formedgroove, and quickly detachable means for securing the annular bodymembers together.

8. Tube-forming apparatus of the class ,de-

scribed comprising a circular body adapted to receive an unvulcanizedinner tube and to support the same in inflated condition, said circularbody including means for limiting contraction of the inner periphery ofthe tube'and means for limiting expansion of the sde portions of thetube without engaging the outer peripheral portion thereof.

GEORGE E. DISNEY.

